Pad structure for paperboard containers



Oct. 8, 1957 l. E. WRIGHT EIAL 3 3 PAD STRUCTURE FOR PAPERBOARD CONTAINERS Filed Oct. 12, 1955 2 Sheets-Sheet 1 INVENTOR. @370;

BY j a a 7 wwwce United States Patent 2,808,978 Patented Oct. 8, 1957 PAD STRUCTURE FOR PAPERBOARD CONTAINERS Ivan E. Wright, Des Plaines, and Vincent J. Annel, Qak Lawn, Ili., assignors to Stone Container Corporation, Chicago, EL, a corporation of Illinois Application October 12, 1955, Serial No. 540,046

2 Claims. (Cl. 229-44) This invention relates generally to the construction of pads for the ends of paperboard containers, especially of corrugated board, and more particularly is concerned with novel spacing structure for paperboard containers.

The structure of this invention, while described in connection with end pad constructions, is applicable to constructions where a pad is positioned intermediate the ends of a container, but it has especial advantages for end pad use which will become apparent as the description proceeds.

Uniform freight regulations require spacing and padding under certain circumstances which must be accomplished for compliance, even at increased packaging expense. In this invention, and it is an object so to provide, spacing from side or vertical walls and end padding is accomplished through the use of a single formation which is easy to form and assemble and which is highly economical.

It has been customary in the packaging art, where the package is formed of corrugated board in particular, to form the spacing members of glued stacks or blocks of paperboard strips in order to achieve strength and protective padding. These are expensive to produce and in addition make the package heavy. Likewise they require glueing apparatus and additional labor to assemble. This invention contemplates the elimination of much of the expense of manufacturing and installing such spacing members, called build-ups in the trade, and likewise to eliminate the apparatus and labor needed for assembling the same, as well as cutting down on the weight of the resulting structure.

A further object of the invention is to provide a pad structure for a paperboard container which accomplishes spacing and padding, but with great strength and economy of manufacture and assembly.

Many other advantages flow from the invention, such as for example, the eliminating of waste in the production of the pad structure since there is absolutely no scrap in forming the structure of the invention; the provision of a pad structure which is capable of being assembled without erection, so that pads may be stored or shipped perfectly fiat and immediately erected or set up when desired for use; and the provision of air spaces in the resulting package. These and otheradvantages and objects will become apparent as the description of the invention proceeds in connection with which there has been described and illustrated a preferred embodiment of the invention only by Way of example and not limitation, to enable those skilled in the art to appreciate the advances made and know how to construct and practice the invention.

In the drawings:

Fig. 1 is a perspective exploded view of the top portion of a paperboard container in the process of being assembled, using an' end pad having the construction of the invention along at least one side edge thereof.

Fig. 2 is a median sectional view through the assembled paperboard container of Fig. 1 showing the manner in which the end pad is assembled therein.

Fig. 3 is a bottom perspective view of the edge of the end pad having the construction of the invention.

Fig. 4 is a top plan view of the edge of the end pad of Fig. 3 developed to show the manner of formation thereof.

Fig. 5 is a perspective view of a section of the formation comprising invention taken at a place where a tab is positioned in assembled condition.

Fig. 6 is a median sectional view taken through the structure along the length thereof.

As stated above the usual spacing and padding structures for paperboard containers are in the form of buildups, which may conveniently be constructed of scraps, if available, of corrugated sheeting glued together to form blocks. In the structure which is described and illustrated, the invention is applied only to one edge of an end pad for a corrugated container. The other edges of the container could as easily be formed in the same manner, but for some particular purposes may not be required to be formed as the invention dictates. Furthermore the illustration of different structures illustrates the prior devices.

In Figs. 1 and 2 there is illustrated a paperboard carton 16 in which an article of merchandise, such as for example a household appliance 12 is disposed for storage or shipment. The particular appliance may be radio or television receiver, a refrigerator, or a range and may have some manner of protuberance such as a knob or dial or vent such as for example indicated at 14 which requires that the adjacent wall 16 of the carton 10 be spaced therefrom and padded. Perhaps the other faces of the appliance 12 need spacing and padding but not to the same extent. The upper end of the container 10 is provided with conventional closure flaps 18 adapted to be folded down upon the completed package to enclose the same as shown in Fig. 2, and sealed by tape 22 or the like.

In Fig. 1 there is illustrated an end pad designated generally 24 which is poised for insertion into the top of the carton it on the upper end of the appliance 12 to protect the same and also provide the necessary spacing from the walls of the carton. The pad 24 is generally rectangular in the particular illustration, and each of its four sides has a different formation for padding and spa'c: ing purposes. The pad is formed principally of a generally rectangular sheet 26 of paperboard having one edge 28 without any folded or cut parts, but provided with a large block 30 built up of strips of paperboard glued together. This is one form of padding and spacing, and the particular build-up is of a length substantially less than the length of the side edge 28. In view of the expense of this type of padding, wherever possible, a full length is not used. The block is glued to the bottom surface of the sheet 26 flush with the edge 28.

The opposite edge of the rectangular sheet 26 has an elongate strip 32 integral with the sheet 26 and secured along a hinged fold 34. A rectangular block 36 of paperboard is glued to the outer surface thereof so that when the strip is folded to its normally vertical position, the build-up 36 will face the outside of the pad 24, engaging the rear wall 38 of the carbon 10. Because of the formations on the other sides of pad 24, the fold 34 does not extend completely from end to end but is shortened by cuts 40 made to facilitate the bending of portions of the said formations.

The formation 42 on the far side edge as viewed in Fig. l is provided by having an elongate strip 44 folded down along the fold line 46, bent at right angles as at 48 upward to form another elongate strip 59 parallel with and spaced from strip 44, and terminating in another horizontal right angle folded strip 52 glued to the top of the sheet 26 along the edge. The formation is integral with the sheet, and provides an elongate space which has a reenforcing block 54 of glued paperboard therein.

The three diiferent forrnations described could all be made with the structure of the invention now to be set forth, if desired, or opposite or adjacent edges could be so constructed.

The construction of the invention is designated generally 60 and is formed on the side opposite the formation 42. Formation 6G is integral with the sheet 26, and as shown in Fig. 4 is formed of four elongate parallel integral strips 62,- 64, 66 and 68 conected along their longer edges by the folds 70, '72, 74 and 76. The strips 62 and 66 are equal in width and comprise the side walls of the formation 60; the strip 64 together with an equal width portion of the strip 68 adjacent the fold 76 form respectively the bottom and top walls of the formation 60;and the remaining portion 78 of the strip 68 overlies the top surface of the sheet 26 and is secured thereto as for example by glue to retain the formation in assembly. V

The strip 64 is provided along its length with die-cut tabs 80 of any convenient number, each tab 80 being out along three lines 81, 82 and 83 and being of the same width as the strip 64. The remaining side of each tab is hingedly connected to the body of the strip 64 along a fold or hinge line 84, the length of the tab 80 from hinge line 84 to the cut edge 82 being substantially the same length as the width of the sides 62 and 66. The out line 82 is provided with an outwardly offset portion, giving rise to the formation of a tongue 86 which makes the overall length of the resulting tab 86 slightly more than the width of the strips 62 and 66.

The tabs may face either end of the strip 64, although in the structure illustrated, there are two connected to the strip 64 at their left hand ends and one at its right hand end (Fig. 4).

' The strip 68 has transverse die cut slots 88 therein, positioned along the length thereof at the same place that the hinge folds 84 occur along the length of the strip 64. The slots 88 are slightly longer than the tongues 86 and are centered relative to the formation 60 when erected.

As seen in Fig. 3, in assembling the formation 60, the wall or strip 62 is folded downward along its fold line 70, the strip 64 is then folded at right angle to the wall 62 along the fold line 72 away from the body of the sheet 26, the outer wall or strip 66 folded upward along the fold line 74, the outer strip 68 is folded horizontally along the fold line 76 to close the hollow 90 formed on the interior of the formation 68 and the edge portion 78 is secured to the top surface of sheet 26 along the edge thereof. In the resulting formation which is an open ended rectangular cross section elongate tube, there is no support to prevent the same from being collapsed substantially flat in the plane of the sheet 26. This enables the end pad 24, at least insofar as the formation 60 is concerned, to be flattened for storage or shipment. To erect the structure, one merely moves the formation 60 to its rectangular cross section and proceeds as described below.

Each of the tabs 80 is now pushed out of its recess in the strip into the hollow 90 and swung about its hinged connection 84 until disposed at a right angle to the length of the tubular formation. The tongue 86 will snap into the appropriate slot 88 locking the tab in place and, since the overall configuration and dimensions of the tabs are substantially the same as those of the tubular formation, the formation 60 will thereby be firmly erected and stiffened along its length with spaced transverse partitions or Walls firmly engaged and locked on the interior.

The resulting structure is of unusual strength and will resist crushing and absorb shock. The top of the pad has a double thickness because of the overlapping of the part 78. The application of crushing pressure from the opposite ends of the tubular formation 60 is of course resisted by an extremely strong column of paperboard. Crushing from the sides is resisted since the tabs are all edgewise to pressure and support the side walls of the formation serving as spaced load-bearing partitions along the length of the tubular formation.

In case the pad 24 is formed of corrugated board, it is preferable that the corrugations be aligned as indicated by the arrow in Fig. 1, that is at right angle to the tubular formation 60. Thus, the tabs 80 will also have the lines of corrugation across their narrow dimension, and present much stronger edges to crushing pressure from the side.

The ordinary paperboard carton for use with merchandise requiring padding and spacers is usually a oneuse" container, discarded after the merchandise has been received and removed from its package. As such it is desirable that same be economical while performing its intended functions efiiciently, and the end pad of the invention is admirably suited for economical manufacture. The invention is advantageous in another respect, however, in that if the carton and its end pad is intended to be used again, it is a simple matter to collapse the formation 60 by pushing the tabs 80 back to their original positions in the plane of the strip 64 and flattening the formation. The tabs may be pushed by using any elongate instrument such as a wooden slat or the like inserted into the tube. Erection afterward is a relatively simple matter.

In order to assist in erection of the tabs 80 within the tubular formation, '60, one or more finger holes may be punched in the strip 68 as shown at 96 in Figs. 1 and 4. These holes enable facile manipulation of the tabs 80, not only for erection, but for collapse as well. If desired these holes may be demarked along weakened lines, to enable the user to push the center of the opening inward when the device is to be erected. 7

Several variations should be pointed out. In the first place, the exact cross sectional configuration of the formation 60 need not be rectangular but can as well be quadrangular, with various combinations of proportions for the dimensions of the sides. Preferably, the shape of the tabs will be the identical shape as the cross section of the formation.

The carton 10 illustrated is shown having only four walls, so that the sheet member 26 is a rectangular shape. Obviously some articles may require other configurations of cartons, and hence the shape of the sheet member 26 will likewise vary, and may not be four sided. The only requirement for the invention is that the structure be formed on a straight edge, or on a part thereof.

It is believed that the invention has been fully explained to eliminate the need for further discussion. Considerable variation is capable of being made in the minor details, proportions and dimensions of the invention without in any way departing from the spirit or scope thereof, as defined and set forth in the appended claims.

What it is desired to claim by Letters Patent of the United States is:

1. An end pad structure comprising, a rectangular stiff paperboard sheet having four strips integrally connected thereto along a side edge thereof and separated by lines of fold, said strips being folded into an openended tube of substantially rectangular cross-section coextensive with said side edge and upstanding from one surface of the sheet, there being a first strip arranged parallel with and spaced above said one surface, a second strip substantially parallel With the first strip and said sheet, a third strip perpendicular to said first and second strips and connected with said sheet and first strip, and a fourth strip parallel with the third strip and connected with said first and second strips, said third and fourth strips being spaced apart a distance equal to the width of said first and second strips and said first and second strips being substantially equal in width, said first strip having intermittently spaced and hinged tabs integral therewith bent at right angles to said first strip, said tabs each being substantially equal in size to the cross-section of the tube and having the edge thereof opposite its hinged connection abutting the facing surface of said second strip, said free edge having an intermediate tongue extending therefrom and said second strip having transverse slots therein each receiving a said tongue therein to lock said tabs in position at right angles to the longitudinal axis of the tube. a

5 posite to that from which the tube is upstanding.

References Cited in the file of this patent UNITED STATES PATENTS 2,076,844 Holmes Apr. 13, 1937 2,250,491 Lurrain July 29, 1941 2,444,183 Cahners June 29, 1948 

